for_all p s checks if all elements of the set satisfy the predicate p .

val exists : (elt -> bool) -> t -> bool

exists p s checks if at least one element of the set satisfies the predicate p .

val filter : (elt -> bool) -> t -> t

filter p s returns the set of all elements in s that satisfy predicate p . If p satisfies every element in s , s is returned unchanged (the result of the function is then physically equal to s ).

Before4.03 Physical equality was not ensured.

val partition : (elt -> bool) -> t -> t * t

partition p s returns a pair of sets (s1, s2) , where s1 is the set of all the elements of s that satisfy the predicate p , and s2 is the set of all the elements of s that do not satisfy p .

val cardinal : t -> int

Return the number of elements of a set.

val elements : t -> elt list

Return the list of all elements of the given set. The returned list is sorted in increasing order with respect to the ordering Ord.compare , where Ord is the argument given to Set.Make .

val min_elt : t -> elt

Return the smallest element of the given set (with respect to the Ord.compare ordering), or raise Not_found if the set is empty.

val max_elt : t -> elt

Same as Set.S.min_elt , but returns the largest element of the given set.

val choose : t -> elt

Return one element of the given set, or raise Not_found if the set is empty. Which element is chosen is unspecified, but equal elements will be chosen for equal sets.

val split : elt -> t -> t * bool * t

split x s returns a triple (l, present, r) , where l is the set of elements of s that are strictly less than x ; r is the set of elements of s that are strictly greater than x ; present is false if s contains no element equal to x , or true if s contains an element equal to x .

val find : elt -> t -> elt

find x s returns the element of s equal to x (according to Ord.compare ), or raise Not_found if no such element exists.

Since 4.01.0

val of_list : elt list -> t

of_list l creates a set from a list of elements. This is usually more efficient than folding add over the list, except perhaps for lists with many duplicated elements.